U.S. patent number 4,655,954 [Application Number 06/767,570] was granted by the patent office on 1987-04-07 for low phosphate or phosphate free nonaqueous liquid nonionic laundry detergent composition and method of use.
This patent grant is currently assigned to Colgate-Palmolive Company. Invention is credited to Danielle Bastin, Guy Broze, Leo Laitem, Trazollah Ouhadi.
United States Patent |
4,655,954 |
Broze , et al. |
April 7, 1987 |
Low phosphate or phosphate free nonaqueous liquid nonionic laundry
detergent composition and method of use
Abstract
A low polyphosphate or a polyphosphate free liquid heavy duty
laundry detergent composition comprising a suspension of an alkali
metal polyacetal carboxylic acid builder salt in liquid nonionic
surfactant. The laundry detergent composition comprises a
nonaqueous liquid nonionic surfactant containing a stable
suspension of an alkali metal polyacetal carboxylic acid builder
salt.
Inventors: |
Broze; Guy (Grace-Hollogne,
BE), Bastin; Danielle (Soumagne, BE),
Laitem; Leo (Orp-Jauche, BE), Ouhadi; Trazollah
(Liege, BE) |
Assignee: |
Colgate-Palmolive Company (New
York, NY)
|
Family
ID: |
25079885 |
Appl.
No.: |
06/767,570 |
Filed: |
August 20, 1985 |
Current U.S.
Class: |
510/304; 510/306;
510/307; 510/321; 510/325; 510/338; 510/467; 510/476; 510/479;
510/488 |
Current CPC
Class: |
C11D
3/3703 (20130101); C11D 17/0004 (20130101); C11D
3/3765 (20130101) |
Current International
Class: |
C11D
17/00 (20060101); C11D 3/37 (20060101); C11D
001/74 (); C11D 003/37 (); C11D 003/39 () |
Field of
Search: |
;252/95,99,102,104,135,174.12,174.23,174.24,547,546,174.16,174.11,DIG.17,DIG.2 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
|
|
|
|
|
15024 |
|
Sep 1980 |
|
EP |
|
117569 |
|
Sep 1984 |
|
EP |
|
Primary Examiner: Willis; Prince E.
Attorney, Agent or Firm: Sylvester; Herbert S. Grill; Murray
M. Blumenkopf; Norman
Claims
What is claimed is:
1. A nonaqueous liquid heavy duty laundry detergent composition
which comprises
20 to 60 percent of at least one liquid nonionic surfactant
detergent,
5 to 50 percent of an organic polyacetal carboxylate builder
salt,
2 to 30 percent of a polycarboxylic acid terminated nonionic
surfactant anti-gel agent and
0 to 2.0 percent of a C.sub.8 to C.sub.20 alkanol phosphoric acid
ester stabilizing agent.
2. The detergent composition of claim 1 comprising one or more
detergent adjuvants selected from the group consisting of bleaching
agent, bleach activator, optical brightener, enzymes and
perfume.
3. The detergent composition of claim 1 comprising 10 to 30 percent
of a polyacetal carboxylate detergent builder salt.
4. The detergent composition of claim 1 comprising 10 to 25 percent
of a polycarboxylic acid terminated surfactant.
5. The detergent composition of claim 1 comprising 0.10 to 2.0
percent of a C.sub.16 to C.sub.18 alkanol phosphoric acid
ester.
6. The detergent composition of claim 1 wherein the polyacetal
carboxylate has the formula: ##STR8## wherein M is selected from
the group consisting of alkali metal, ammonium, alkyl groups having
1 to 4 carbon atoms; tetralkyl ammonium groups and alkanol amine
groups having from 1 to 4 carbon atoms in the alkyl chain; n is at
least 4, and R.sub.1 and R.sub.2 are selected to be individually
stable groups which stabilize the polymer against depolymerization
in alkaline solution and are selected to be compatible with the
ingredients of the nonionic liquid detergent composition.
7. The detergent composition of claim 1 wherein the detergent
builder particles in the nonionic surfactant have a particle size
distribution such that no more than about 10% by weight of said
particles have a particle size of more than about 10 microns.
8. The laundry detergent composition of claim 1 which is
polyphosphate free or low polyphosphate and which comprises
at least one liquid nonionic surfactant in an amount of about 25 to
50%,
a polycarboxylic acid-terminated nonionic surfactant in an amount
of about 10 to 25%,
a polyacetal carboxylate builder in an amount of about 10 to
30%,
a polyphosphate detergent builder in an amount of about 0 to 20%,
and
a C.sub.16 to C.sub.18 alkanol phosphoric acid ester in an amount
of about 0.1 to 1.0%.
9. The laundry detergent composition of claim 8 additionally
comprising
an alkali metal perborate monohydrate bleaching agent in an amount
of about 5 to 30%,
tetraacetylethylene diamine bleach activator in an amount of about
5 to 20%, and
one or more detergent adjuvants selected from the group consisting
of optical brighteners, enzymes and perfume.
10. The laundry detergent composition of claim 8 where the
detergent builder comprises the sodium salt of polyacetal
carboxylic acid.
11. The detergent composition of claim 8 wherein the polyacetal
carboxylate has the formula: ##STR9## wherein M is an alkali metal;
n is 50 to 200, and R.sub.1 and R.sub.2 are selected to be
individually stable groups which stabilize the polymer against
depolymerization in alkaline solution and are selected to be
compatible with the ingredients of the nonionic liquid detergent
composition.
12. The laundry detergent composition of claim 8 where the alkanol
phosphoric acid ester comprises a C.sub.16 to C.sub.18 alkanol
ester of phosphoric acid.
13. The laundry detergent composition of claim 8 which is pourable
at high and low temperatures, is stable in storage and does not gel
when mixed with cold water.
14. The detergent composition of claim 8 which comprises a
polyphosphate builder salt in an amount of about 5 to 15
percent.
15. A phosphate detergent builder free nonaqueous liquid heavy duty
laundry detergent composition which comprises
Nonionic surfactant in an amount of about: 30-45%
A polycarboxylic acid Terminated surfactant in an amount of about:
2-18%
Sodium salt of polyacetal carboxylic acid in an amount of about:
5-22%
C.sub.16 to C.sub.18 alkanol ester of phosphoric acid in an amount
of about: 0.1-0.9%
Sodium perborate monohydrate bleaching agent in an amount of about:
7-22%
Tetraacetylethylene diamine (TAED) bleach activator in an amount of
about: 4-22%.
16. The detergent composition of claim 15 wherein the polyacetal
carboxylate has the formula: ##STR10## wherein M is selected from
the group consisting of sodium and potassium; n is 50 to 200;
R.sub.1 is ##STR11## or mixtures thereof and R.sub.2 is ##STR12##
and the polyacetal carboxylate segments comprise 50 to 80 percent
by weight of the total polyacetal carboxylate.
17. The detergent composition of claim 16 wherein the polyacetal
carboxylate is the sodium salt.
18. A method for cleaning soiled fabrics which comprises contacting
the soiled fabrics with an effective cleaning amount of the laundry
detergent composition of claim 1.
19. A method for cleaning soiled fabrics which comprises contacting
the soiled fabrics with an effective cleaning amount of the laundry
detergent composition of claim 8.
20. A method for cleaning soiled fabrics which comprises contacting
the soiled fabrics with an effective cleaning amount of the laundry
detergent composition of claim 15.
Description
BACKGROUND OF THE INVENTION
(1) Field of Invention
This invention relates to nonaqueous liquid fabric treating
compositions. More particularly, this invention relates to
phosphate free or low phosphate nonaqueous liquid laundry detergent
compositions containing a suspension of a polyacetal carboxylate
builder salt in nonionic surfactants which compositions are stable
against phase separation and gelation and are easily pourable and
to the use of these compositions for cleaning soiled fabrics.
(2) Discussion of Prior Art
Liquid nonaqueous heavy duty laundry detergent compositions are
well known in the art. For instance, compositions of that type may
comprise a liquid nonionic surfactant in which are dispersed
particles of a builder, as shown for instance in the U.S. Pat. Nos.
4,316,812, 3,630,929 and 4,264,466 and British Pat. Nos. 1,205,711,
1,270,040 and 1,600,981.
The related pending applications assigned to the common assignee
are Ser. No. 687,815, filed Dec. 31, 1984; Ser. No. 597,793, filed
Apr. 6, 1984; now abandoned Ser. No. 597,948, filed Apr. 9, 1984;
and now abandoned Ser. No. 725,455, filed Apr. 22, 1985.
These applications are directed to liquid nonaqueous nonionic
laundry detergent compositions.
The washing power of synthetic nonionic surfactant detergents in
laundry detergent compositions can be increased by the addition of
builders. Sodium tripolyphosphate is one of the preferred builders.
However, the use of sodium polyphosphate in dry powder detergents
does involve several disadvantages such as, for example, the
tendency of the polyphosphates to hydrolyse into pyro- and
ortho-phosphates which represent less valuable builders.
In addition the polyphosphate content of laundry detergents has
been blamed for the undesirably high phosphate content of surface
water. An increased phosphate content in surface water has been
found to contribute towards greater algea growth with the result
that the biological equilibrium of the water can be adversely
altered.
Recently enacted government legislation has been directed to
reducing the amount of polyphosphates present in laundry detergents
and in some jurisdictions in which polyphosphates have been a
problem to require that the laundry detergents not contain any
polyphosphate builders.
Liquid detergents are often considered to be more convenient to
employ than dry powdered or particulate products and, therefore,
have found substantial favor with consumers. They are readily
measurable, speedily dissolved in the wash water, capable of being
easily applied in concentrated solutions or dispersions to soiled
areas on garments to be laundered and are non-dusting, and they
usually occupy less storage space. Additionally, the liquid
detergents may have incorporated in their formulations materials
which could not stand drying operations without deterioration,
which materials are often desirably employed in the manufacture of
particulate detergent products. Although they are possessed of many
advantages over unitary or particulate solid products, liquid
detergents often have certain inherent disadvantages too, which
have to be overcome to produce acceptable commercial detergent
products. Thus, some such products separate out on storage and
others separate out on cooling and are not readily redispersed. In
some cases the product viscosity changes and it becomes either too
thick to pour or so thin as to appear watery. Some clear products
become cloudy and others gel on standing.
In addition to the problem of settling or phase separation the
nonaqueous liquid laundry detergents based on liquid nonionic
surfactants suffer from the drawback that the nonionics tend to gel
when added to cold water. This is a particularly important problem
in the ordinary use of European household automatic washing
machines where the user places the laundry detergent composition in
a dispensing unit (e.g. a dispensing drawer) of the machine. During
the operation of the machine the detergent in the dispenser is
subjected to a stream of cold water to transfer it to the main body
of wash solution. Especially during the winter months when the
detergent composition and water fed to the dispenser are
particularly cold, the detergent viscosity increases markedly and a
gel forms. As a result some of the composition is not flushed
completely off the dispenser during operation of the machine, and a
deposit of the composition builds up with repeated wash cycles,
eventually requiring the user to flush the dispenser with hot
water.
The gelling phonomenon can also be a problem whenever it is desired
to carry out washing using cold water as may be recommended for
certain synthetic and delicate fabrics or fabrics which can shrink
in warm or hot water.
The tendency of concentrated detergent compositions to gel during
storage is aggrevated by storing the compositions in unheated
storage areas, or by shipping the compositions during winter months
in unheated transportation vehicles.
Partial solutions to the gelling problem have been proposed, for
example, by diluting the liquid nonionic with certain viscosity
controlling solvents and gel-inhibiting agents, such as lower
alkanols, e.g. ethyl alcohol (see U.S. Pat. No. 3,953,380), alkali
metal formates and adipates (see U.S. Pat. No. 4,368,147), hexylene
glycol, polyethylene glycol, etc. and nonionic structure
modification and optimization. As an example of nonionic surfactant
modification one particularly successful result has been achieved
by acidifying the hydroxyl moiety end group of the nonionic
molecule. The advantages of introducing a carboxylic acid at the
end of the nonionic include gel inhibition upon dilution;
decreasing the nonionic pour point; and formation of an anionic
surfactant when neutralized in the washing liquor. Nonionic
structure optimization has centered on the chain length of the
hydrophobic-lipophilic moiety and the number and make-up of
alkylene oxide (e.g. ethylene oxide) units of the hydrophilic
moiety. For example, it has been found that a C.sub.13 fatty
alcohol ethoxylated with 8 moles of ethylene oxide presents only a
limited tendency to gel formation.
Nevertheless, improvements are desired in both the stability and
gel inhibition of low phosphate and phosphate free nonaqueous
liquid fabric treating compositions.
BRIEF DESCRIPTION OF THE INVENTION
In accordance with the present invention a highly concentrated low
phosphate, more particularly a polyphosphate detergent builder
free, nonaqueous liquid laundry detergent composition is prepared
by dispersing polyacetal carboxylate builder salt in a liquid
nonionic surfactant detergent.
The polyacetal carboxylate salts used in accordance with the
present invention are well known. The method of making the builder
salts is described in Crutchfield et al U.S. Pat. Nos. 4,315,092
and 4,144,226 and the use of the polyacetal carboxylates as
detergent builder salts is described in Crutchfield et al U.S. Pat.
No. 4,146,495. The disclosure of these three patents is
incorporated herein by reference.
The polyacetal carboxylates are water soluble and will depolymerize
rapidly in neutral or nonalkaline medium to form low molecular
weight components which are readily biodegradable. The polyacetal
carboxylates are accordingly used in formulations which on addition
to wash water normally have a pH of above pH7, e.g. about pH8 to
10, such as pH9 to 10. Though the polyacetal carboxylates as used
in an alkaline medium are effective detergent builder salts, when
the aqueous wash waste water is discharged into a sewer or other
waste water system and the wash water neutralized, the polyacetal
carboxylates are depolymerized into small fragments which are
readily biodegradable. The polyacetal carboxylates are particularly
good detergent builder salts because of their high sequestering
capacity for calcium and magnesium ions in the wash water.
The polyacetal carboxylate detergent builder salts used in the
present invention have the general formula ##STR1## wherein M is an
alkali or ammonium cation, n is at least 4, and R.sub.1 and R.sub.2
are selected to be individually stable groups which stabilize the
polymer against depolymerization in alkaline solution and are
selected to be compatible with the ingredients of the nonionic
liquid detergent composition of the present invention.
A commercially available polyacetal carboxylate detergent builder
salt is sold by Monsanto Chemical Company under the tradename
Builder U and is a sodium salt.
In order to improve the viscosity characteristics of the
composition an acid terminated nonionic surfactant can be added. To
further improve the viscosity characteristics of the composition
and the storage properties of the composition there can be added to
the composition viscosity improving and anti gel agents such
alkylene glycol mono alkyl ethers and anti settling agents such as
phosphoric acid esters and aluminum stearate. In preferred
embodiment of the invention the detergent composition contains an
acid terminated nonionic surfactant and/or an alkylene glycol mono
alkyl ether, and an anti settling agent.
Sanitizing or bleaching agents and activators therefore can be
added to improve the bleaching and cleansing characteristics of the
composition.
In an embodiment of the invention the builder components of the
composition are ground to a particle size of less than 100 microns
and to preferably less than 10 microns to further improve the
stability of the suspension of the builder components in the liquid
nonionic surfactant detergent.
In addition other ingredients can be added to the composition such
as anti-incrustation agents, anti-foam agents, optical brighteners,
enzymes, anti-redeposition agents, perfume and dyes.
The presently manufactured washing machines for home use normally
operate at washing temperatures of up to 95.degree. C. About 20
liters of water are used during the wash and rinse cycles.
About 175 gms of powder detergent per wash is normally used.
In accordance with the present invention where the highly
concentrated liquid detergent is used normally only about 80 gms
(67 ml) or less of the liquid detergent composition is required to
wash a full load of dirty laundry.
Accordingly, in one aspect the present invention there is provided
a phosphate builder free or substantially phosphate builder free
liquid heavy duty laundry composition composed of a suspension of
an alkali metal polyacetal carboxylic acid builder salt in liquid
nonionic surfactant.
According to another aspect, the invention provides a phosphate
free or low phosphate concentrated liquid heavy duty laundry
detergent composition which is stable, non-settling in storage and
non-gelling in storage and in use. The liquid compositions of the
present invention are easily pourable, easily measured and easily
put into the washing machine.
According to another aspect, the invention provides a method for
dispensing a phosphate free or low phosphate liquid nonionic
laundry detergent composition into and/or with cold water without
undergoing gelation. In particular, a method is provided for
filling a container with a nonaqueous liquid laundry detergent
composition in which the detergent is composed, at least
predominantly, of a polyphosphate builder free liquid nonionic
surface active agent and for dispensing the composition from the
container into an aqueous wash bath, wherein the dispensing is
effected by directing a stream of unheated water onto the
composition such that the composition is carried by the stream of
water into the wash bath.
ADVANTAGES OVER THE PRIOR ART
The polyphosphate builder free detergent compositions overcome the
problem of phosphate pollution of surface water.
The polyphosphate free or low polyphosphate concentrated nonaqueous
liquid nonionic surfactant laundry detergent compositions of the
present invention have the added advantages of being stable,
non-settling in storage, and non-gelling in storage. The liquid
compositions are easily pourable, easily measured and easily put
into the laundry washing machines.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide a low
polyphosphate, more particularly a polyphosphate free non-polluting
liquid heavy duty nonaqueous nonionic detergent composition
containing polyacetal carboxylate builder salt suspended in a
nonionic surfactant.
It is another object of the invention to provide a polyphosphate
free or low polyphosphate liquid fabric treating compositions which
are suspensions of polyacetal carboxylate builder salt in a
nonaqueous liquid and which are storage stable, easily pourable and
dispersible in cold, warm or hot water.
Another object of this invention is to formulate a polyphosphate
free or low polyphosphate highly built heavy duty nonaqueous liquid
nonionic surfactant laundry detergent compositions which can be
poured at all temperatures and which can be repeatedly dispersed
from the dispensing unit of European style automatic laundry
washing machines without fouling or plugging of the dispenser even
during the winter months.
Another object of this invention is to provide a polyphosphate free
or low polyphosphate non-gelling, stable suspensions of heavy duty
built nonaqueous liquid nonionic laundry detergent composition
which include an effective amount of polyacetal carboxylate builder
salt.
A further object of this invention is to provide non-gelling,
stable suspensions of heavy duty built nonaqueous liquid nonionic
laundry detergent composition which include an amount of phosphoric
acid alkanol ester and/or aluminum fatty acid salt which is
sufficient to increase the stability of the composition, i.e.
prevent settling of builder particles, etc., preferably while
reducing or at least without increasing the plastic viscosity of
the composition.
These and other objects of the invention which will become more
apparent from the following detailed description of preferred
embodiments are generally provided for by preparing a low
polyphosphate or polyphosphate free detergent builder composition
by adding to the nonaqueous liquid nonionic surfactant an effective
amount of an alkali metal polyacetal carboxylate builder salt and
inorganic or organic fabric treating additives, e.g. viscosity
improving and anti-gel agents, anti-settling agents,
anti-incrustation agents, bleaching agents, bleach activators,
anti-foam agents, optical brighteners, enzymes, anti-redeposition
agents, perfume and dyes.
Nonionic Surfactant Detergent
The nonionic synthetic organic detergents employed in the practice
of the invention may be any of a wide variety of such compounds,
which are well known.
As is well known, the nonionic synthetic organic detergents are
characterized by the presence of an organic hydrophobic group and
an organic hydrophilic group and are typically produced by the
condensation of an organic aliphatic or alkyl aromatic hydrophobic
compound with ethylene oxide (hydrophilic in nature). Practically
any hydrophobic compound having a carboxy, hydroxy, amido or amino
group with a free hydrogen attached to the nitrogen can be
condensed with ethylene oxide or with the polyhydration product
thereof, polyethylene glycol, to form a nonionic detergent. The
length of the hydrophilic or polyoxy ethylene chain can be readily
adjusted to achieve the desired balance between the hydrophobic and
hydrophilic groups. Typical suitable nonionic surfactants are those
disclosed in U.S. Pat. Nos. 4,316,812 and 3,630,929.
Usually, the nonionic detergents are poly-lower alkoxylated
lipophiles wherein the desired hydrophile-lipophile balance is
obtained from addition of a hydrophilic poly-lower alkoxy group to
a lipophilic moiety. A preferred class of the nonionic detergent
employed is the poly-lower alkoxylated higher alkanol wherein the
alkanol is of 9 to 18 carbon atoms and wherein the number of mols
of lower alkylene oxide (of 2 or 3 carbon atoms) is from 3 to 12.
Of such materials it is preferred to employ those wherein the
higher alkanol is a higher fatty alcohol of 9 to 11 or 12 to 15
carbon atoms and which contain from 5 to 8 or 5 to 9 lower alkoxy
groups per mol. Preferably, the lower alkoxy is ethoxy but in some
instances, it may be desirably mixed with propoxy, the latter, if
present, often being a minor (less than 50%) proportion.
Exemplary of such compounds are those wherein the alkanol is of 12
to 15 carbon atoms and which contain about 7 ethylene oxide groups
per mol, e.g. Neodol 25-7 and Neodol 23-6.5, which products are
made by Shell Chemical Company, Inc. The former is a condensation
product of a mixture of higher fatty acohols averaging about 12 to
15 carbon atoms, with about 7 mols of ethylene oxide and the latter
is a corresponding mixture wherein the carbon atom content of the
higher fatty alcohol is 12 to 13 and the number of ethylene oxide
groups present averages about 6.5. The higher alcohols are primary
alkanols.
Other examples of such detergents include Tergitol 15-S-7 and
Tergitol 15-S-9, both of which are linear secondary alcohol
ethoxylates made by Union Carbide Corp. The former is mixed
ethoxylation product of 11 to 15 carbon atoms linear secondary
alkanol with seven mols of ethylene oxide and the latter is a
similar product but with nine mols of ethylene oxide being
reacted.
Also useful in the present composition as a component of the
nonionic detergent are higher molecular weight nonionics, such as
Neodol 45-11, which are similar ethylene oxide condensation
products of higher fatty alcohols, with the higher fatty alcohol
being of 14 to 15 carbon atoms and the number of ethylene oxide
groups per mol being about 11. Such products are also made by Shell
Chemical Company.
Other useful nonionics are represented by the commercially well
known class of nonionics sold under the trademark Plurafac. The
Plurafacs are the reaction product of a higher linear alcohol and a
mixture of ethylene and propylene oxides, containing a mixed chain
of ethylene oxide and propylene oxide, terminated by a hydroxyl
group. Examples include products which are (A) C.sub.13 -C.sub.15
fatty alcohol condensed with 6 moles ethylene oxide and 3 moles
propylene oxide, (B) C.sub.13 -C.sub.15 fatty alcohol condensed
with 7 moles propylene oxide and 4 moles ethylene oxide, (C)
C.sub.13 -C.sub.15 fatty alcohol condensed with 5 moles propylene
oxide and 10 moles ethylene oxide, and (D) a 1:1 mixture of (B) and
(C).
Another group of liquid nonionics are commercially available from
Shell Chemical Company, Inc. under the Dobanol trademark: Dobanol
91-5 is an ethoxylated C.sub.9 -C.sub.11 fatty alcohol with an
average of 5 moles ethylene oxide and Dobanol 25-7 is an
ethoxylated C.sub.12 -C.sub.15 fatty alcohol with an average of 7
moles ethylene oxide per mole of fatty alcohol.
In the preferred poly-lower alkoxylated higher alkanols, to obtain
the best balance of hydrophilic and lipophilic moieties the number
of lower alkoxies will usually be from 40% to 100% of the number of
carbon atoms in the higher alcohol, preferably 40 to 60% thereof
and the nonionic detergent will preferably contain at least 50% of
such preferred poly-lower alkoxy higher alkanol. Higher molecular
weight alkanols and various other normally solid nonionic
detergents and surface active agents may be contributory to
gelation of the liquid detergent and consequently, will preferably
be omitted or limited in quantity in the present compositions,
although minor proportions thereof may be employed for their
cleaning properties, etc. With respect to both preferred and less
preferred nonionic detergents the alkyl groups present therein are
generally linear although branching may be tolerated, such as at a
carbon next to or two carbons removed from the terminal carbon of
the straight chain and away from the ethoxy chain, if such branched
alkyl is not more than three carbons in length. Normally, the
proportion of carbon atoms in such a branched configuration will be
minor rarely exceeding 20% of the total carbon atom content of the
alkyl. Similarly, although linear alkyls which are terminally
joined to the ethylene oxide chains are highly preferred and are
considered to result in the best combination of detergency,
biodegradability and non-gelling characteristics, medial or
secondary joinder to the ethylene oxide in the chain may occur. It
is usually in only a minor proportion of such alkyls, generally
less than 20% but, as is in the cases of the mentioned Terigtols,
may be greater. Also, when propylene oxide is present in the lower
alkylene oxide chain, it will usually be less than 20% thereof and
preferably less than 10% thereof.
When greater proportions of non-terminally alkoxylated alkanols,
propylene oxide-containing poly-lower alkoxylated alkanols and less
hydrophile-lipophile balanced nonionic detergent than mentioned
above are employed and when other nonionic detergents are used
instead of the preferred nonionics recited herein, the product
resulting may not have as good detergency, stability, viscosity and
non-gelling properties as the preferred compositions but use of the
viscosity and gel controlling compounds of the invention can also
improve the properties of the detergents based on such nonionics.
In some cases, as when a higher molecular weight poly lower
alkoxylated higher alkanol is employed, often for its detergency,
the proportion thereof will be regulated or limited in accordance
with the results of routine experiments, to obtain the desired
detergency and still have the product non-gelling and of desired
viscosity. Also, it has been found that it is only rarely necessary
to utilize the higher molecular weight nonionics for their
detergent properties since the preferred nonionics described herein
are excellent detergents and additionally, permit the attainment of
the desired viscosity in the liquid detergent without gelation at
low temperatures.
Another useful group of nonionic surfactants are the "Surfactant T"
series of nonionics available from British Petroleum. The
Surfactant T nonionics are obtained by the ethoxylation of
secondary C.sub.13 fatty alcohols having a narrow ethylene oxide
distribution. The Surfactant T5 has an average of 5 moles of
ethylene oxide; Surfactant T7 an average of 7 moles of ethylene
oxide; Surfactant T9 an average of 9 moles of ethylene oxide and
Surfactant T12 an average of 12 moles of ethylene oxide per mole of
secondary C.sub.13 fatty alcohol.
In the compositions of this invention, preferred nonionic
surfactants include the C.sub.13 -C.sub.15 secondary fatty alcohols
with relatively narrow contents of ethylene oxide in the range of
from about 7 to 9 moles, and the C9 to C11 fatty alcohols
ethoxylated with about 5-6 moles ethylene oxide.
Mixtures of two or more of the liquid nonionic surfactants can be
used and in some cases advantages can be obtained by the use of
such mixtures.
Acid Terminated Nonionic Surfactant
The viscosity and gel properties of the liquid detergent
compositions can be improved by including in the composition an
effective amount an acid terminated liquid nonionic surfactant. The
acid terminated nonionic surfactants consist of a nonionic
surfactant which has been modified to convert a free hydroxyl group
thereof to a moiety having a free carboxyl group, such as an ester
or a partial ester of a nonionic surfactant and a polycarboxylic
acid or anhydride.
As disclosed in the commonly assigned copending application Ser.
No. 597,948 filed Apr. 9, 1984, the disclosure of which is
incorporated herein by reference, the free carboxyl group modified
nonionic surfactants, which may be broadly characterized as
polyether carboxylic acids, function to lower the temperature at
which the liquid nonionic forms a gel with water.
The addition of the acid terminated nonionic surfactants to the
liquid nonionic surfactant aids in the dispensibility of the
composition, i.e. pourability, and lowers the temperature at which
the liquid nonionic surfactants form a gel in water without a
decrease in their stability against settling. The acid terminated
nonionic surfactant reacts in the washing machine water with the
alkalinity of the dispersed builder salt phase of the detergent
composition and acts as an effective anionic surfactant.
Specific examples include the half-esters of product (A) with
succinic anhydride, the ester or half ester of Dobanol 25-7 with
succinic anhydride, and the ester or half ester of Dobanol 91-5
with succinic anhydride. Instead of succinic anhydride, other
polycarboxylic acids or anhydrides can be used, e.g. maleic acid,
maleic acid anhydrided, citric acid and the like.
The acid terminated nonionic surfactants can be prepared as
follows:
Acid Terminated product (A). 400 g of product (A) nonionic
surfactant which is a C.sub.13 to C.sub.15 alkanol which has been
alkoxylated to introduce 6 ethyleneoxide and 3 propylene oxide
units per alkanol unit is mixed with 32 g of succinic anhydride and
heated for 7 hours at 100.degree. C. The mixture is cooled and
filtered to remove unreacted succinic material. Infrared analysis
indicated that about one half of the nonionic surfactant has been
converted to the acidic half-ester thereof.
Acid Terminated Dobanol 25-7. 522 g of Dobanol 25-7 nonionic
surfactant which is the product of ethoxylation of a C.sub.12 to
C.sub.15 alkanol and has about 7 ethyleneoxide units per molecule
of alkanol is mixed with 100 g of succinic anhydride and 0.1 g of
pyridine (which acts as an esterification catalyst) and heated at
260.degree. C. for 2 hours, cooled and filtered to remove unreacted
succinic material. Infrared analysis indicates that substantially
all the free hydroxyls of the surfactant have reacted.
Acid Terminate Dobanol 91-5. 1000 of Dobanol 91-5 nonionic
surfactant which is the product of ethoxylation of a C.sub.9 to
C.sub.11 alkanol and has about 5 ethylene oxide units per molecule
of alkanol is mixed with 265 g of succinic anhydride and 0.1 g of
pyridine catalyst and heated at 260.degree. C. for 2 hours, cooled
and filtered to remove unreacted succinic material. Infrared
analysis indicates that substantially all the free hydroxyls of the
surfactant have reacted.
Other esterification catalysts, such as an alkali metal alkoxide
(e.g. sodium methoxide) may be used in place of, or in admixture
with, the pyridine.
The acidic polyether compound, i.e. the acid terminated nonionic
surfactant is preferably added dissolved in the nonionic
surfactant.
BUILDER SALTS
The liquid nonaqueous nonionic surfactant used in the compositions
of the present invention has dispersed and suspended therein fine
particles of organic and/or inorganic detergent builder salts.
The present invention includes as an essential part of the
composition an organic polyacetal carboxylate acid builder
salt.
Organic Builder Salts
The preferred organic builder salts comprises alkali metal salts of
polyacetal carboxylic acid, preferably the sodium and potassium
salts.
Broadly, however, the polyacetal carboxylate detergent builder
salts used in the present invention have the following general
formula ##STR2## wherein M is selected from the group consisting of
alkali metal, ammonium, alkyl groups having 1 to 4 carbon atoms;
tetralkyl ammonium groups and alkanol amine groups having from 1 to
4 carbon atoms in the alkyl chain; the alkali metals are preferred,
for example sodium and potassium; n is at least 4; and R.sub.1 and
R.sub.2 are individually any chemically stable groups. R.sub.1 and
R.sub.2 may be the same or different groups.
The end groups R.sub.1 and R.sub.2 may be selected from a wide
range of materials as long as they stabilize the polyacetal
carboxylate polymer against rapid depolymerization in an alkaline
solution. The R.sub.1 and R.sub.2 end groups are also selected to
be compatible with the ingredients used to formulate the nonaqueous
liquid nonionic composition of the present invention, particularly
the nonionic surfactant and the anti gel and anti settling
agents.
The number of the repeating groups, i.e. the value of n, is an
important factor since the effectiveness of the polyacetal
carboxylate salt as a detergency builder is affected by the polymer
chain length. Where n=4 the polymer shows effectiveness as a
sequestrant, chelating agent and builder. The value for n can be as
high as 400. There does not, however, appear to be any advantage
for n to have a greater value than about 200.
When the value for n exceeds about 100 no significant improvement
in sequestering chelating and builder properties is observed. Thus
the polyacetal carboxylate can contain between 10 and 400 units,
i.e. n can equal 10 to 400, preferably n=50 to 200 and more
preferably n=50 to 100 repeating units.
Where n has a value of 50 to 200 there is provided very good
sequestration effectiveness for calcium and magnesium ions and very
good builder properties.
As an example, suitable chemically stable end groups include stable
substituent moieties derived from otherwise stable compounds, such
as alkanes, such as methane, ethane, propane and butane; alkenes
such as ethylene, propylene and butylene; branched chain
hydrocarbons, both saturated and unsaturated, such as 2-methyl
butane and 2-methyl butene; alcohols such as methanol, ethanol,
2-propanol, cyclohexanol, polyhydric alcohols such as 1,2-ethane
diol and 1,4-benzene diol; ethers such as methoxyethane methyl
ether, ethyl ether, ethoxypropane and cyclic ethers such as
ethylene oxide; epichlorohydrin and tetramethylene oxide; aldehydes
and ketones such as ethanal, acetone, propanal and methylethyl
ketone; and carboxylate containing compounds such as the alkali
metal salts of carboxylic acids, the esters of carboxylic acids and
the anhydrides. Particularly suitable end groups include alkyl
groups and cyclic alkyl groups containing oxygen: such as oxyalkyl
groups like methoxy, ethoxy, carboxylic acids; and aldehydes,
ethers and other oxygen containing alkyl groups.
The polyacetal carboxylates can contain polymer fragments, and
accordingly, the polymer can be a linear homopolymer or copolymer,
or it can be branched. Any number of chain extending agents can be
copolymerized with the polyacetal carboxylates. It is only
necessary that the chain extending agent will provide at least two
reactive sites and does not cause the polyacetal carboxylates to
depolymerize in alkaline solution and that they be compatible with
the nonionic surfactant and the anti-gel and anti settling agents
of the present invention. Suitable chain extending agents include:
polyhydric alcohols, such as ethylene oxide, propylene oxide and
epihalohydrin epoxysuccinates; aldehydes, such as formaldehyde and
acetaldehyde. It is particularly beneficial when the chain
extending agent contains substituent carboxy groups. Aliphatic
chain extending agents having from 1 to 4 carbon atoms, such as
ethylene oxide or propylene oxide, are especially preferred.
When acetal carboxylate esters are copolymerized with a chain
extending agent, the amount of acetal carboxylate should be at
least about 50 percent by weight, based on the total weight of the
polymer, to insure that the polymer will effectively sequester
calcium and magnesium ions and retain its builder properties. It is
preferred that the amount of acetal carboxylate is 50 to 80 percent
such as about 80 percent by weight, based on the total weight of
the polymer, or even higher.
In a preferred embodiment of the invention R.sub.1 is a member
selected from the group consisting of ##STR3## and mixtures there
of, and R.sub.2 is a member selected from the group consisting of
##STR4## and mixtures thereof, where R is hydrogen or alkyl having
1 to 8 carbon atoms, and M is as defined above.
It is particularly preferred that R.sub.1 is ##STR5## or mixtures
thereof, and R.sub.2 is ##STR6## where M is sodium and n is 50 to
200.
Other organic builders that can be used are polymers and copolymers
of polyacrylic acid and polymaleic anhydride and the alkali metal
salts thereof. More specifically such builder salts can consist of
a copolymer which is the reaction product of about equal moles of
methacrylic acid and maleic anhydride which has been completely
neutralized to form the sodium salt thereof. The builder is
commercially available under the tradename of Sokalan CP5. This
builder serves when used even in small amounts to inhibit
encrustation.
Since the compositions of this invention are generally highly
concentrated, and, therefore, may be used at relatively low
dosages, it is desirable to supplement the builder with an
auxiliary builder such as an alkali metal lower polycarboxylic acid
having high calcium and magnesium binding capacity to inhibit
incrustation which could otherwise be caused by formation of
insoluble calcium and magnesium salts. Suitable alkali metal
Polycarboxylic acids are alkali metal salts of citric and tartaric
acid, e.g. monosodium citrate (anhydrous), trisodium citrate,
monosodium and disodium tartrate and dipotassium tartrate.
Examples of organic alkaline sequestrant builder salts which can be
used with the polyacetal carboxylate builder salts or in admixture
with other organic and inorganic builders are alkali metal,
ammonium or substituted ammonium, aminopolycarboxylates, e.g.
sodium and potassium ethylene diaminetetraacetate (EDTA), sodium
and potassium nitriloacetates (NTA) and triethanolammonium
N-(2-hydroxyethyl)nitrilodiacetates. Mixed salts of these
aminopolycarboxylates are also suitable.
Other suitable builders of the organic type include
carboxymethylsuccinates, tartronates and glycollates.
Inorganic Builder Salts
The invention detergent compositions can also include inorganic
water soluble and/or water insoluble detergent builder salts.
Suitable inorganic alkaline builder salts that can be used are
alkali metal carbonate, borates, bicarbonates, and silicates.
(Ammonium or substituted ammonium salts can also be used.) Specific
examples of such salts are sodium carbonate, sodium tetraborate,
sodium bicarbonate, sodium sesquicarbonate and potassium
bicarbonate.
The alkali metal silicates are useful builder salts which also
function to adjust or control the pH and to make the composition
anticorrosive to washing machine parts. Sodium silicates of
Na.sub.2 O/SiO.sub.2 ratios of from 1.6/1 to 1/3.2, especially
about 1/2 to 1/2.8 are preferred. Potassium silicates of the same
ratios can also be used.
Though it is preferred that the detergent composition be phosphate
or polyphosphate free or substantially polyphosphate free, small
amounts of the conventional polyphosphate builder salts can be
added where the local legislation permits such use. Specific
examples of such builder salts are sodium tripolyphosphate (TPP),
sodium pyrophosphate, potassium pyrophosphate, potassium
tripolyphosphate and sodium hexametaphosphate. The sodium
tripolyphosphate (TPP) is a preferred polyphosphate. In the
formulations where the polyphosphate is added it is added in an
amount of 0 to 30%, such as 5 to 15. As mentioned previously,
however, it is preferred that the formulations be polyphosphate
free or substantially polyphosphate free.
Other typical suitable builders include, for example, those
disclosed in U.S. Pat. Nos. 4,316,812, 4,264,466 and 3,630,929. The
inorganic alkaline builder salts can be used with the nonionic
surfactant detergent compound or in admixture with other organic or
inorganic builder salts.
The water insoluble crystalline and amorphous aluminosilicate
zeolites can be used. The zeolites generally have the formula
wherein x is 1, y is from 0.8 to 1.2 and preferably 1, z is from
1.5 to 3.5 or higher and preferably 2 to 3 and w is from 0 to 9,
preferably 2.5 to 6 and M is preferably sodium. A typical zeolite
is type A or similar structure, with type 4A particularly
preferred. The preferred aluminosilicates have calcium ion exchange
capacities of about 200 milliequivalents per gram or greater, e.g.
400 meq lg.
Various crystalline zeolites (i.e. alumino-silicates) that can be
used are described in British Pat. No. 1,504,168, U.S. Pat. No.
4,409,136 and Canadian Pat. Nos. 1,072,835 and 1,087,477, all of
which are hereby incroporated by reference for such descriptions.
An example of amorphous zeolites useful herein can be found in
Belgium Pat. No. 835,351 and this patent too is incorporated herein
by reference.
Other materials such as clays, particularly of the water-insoluble
types, may be useful adjuncts in compositions of this invention.
Particularly useful is bentonite. This material is primarily
montmorillonite which is a hydrated aluminum silicate in which
about 1/6th of the aluminum atoms may be replaced by magnesium
atoms and with which varying amounts of hydrogen, sodium,
potassium, calcium, etc., may be loosely combined. The bentonite in
its more purified form (i.e. free from any grit, sand, etc.)
suitable for detergents contains at least 50% montmorillonite and
thus its cation exchange capacity is at least about 50 to 75 meq
per 100 g of bentonite. Particularly preferred bentonites are the
Wyoming or Western U.S. bentonites which have been sold as
Thixo-jels 1, 2, 3 and 4 by Georgia Kaolin Co. These bentonites are
known to soften textiles as described in British Pat. No. 401,413
to Marriott and British Pat. No. 461,221 to Marriott and Guan.
Viscosity Control and Anti Gel Agents
The inclusion in the detergent composition of an effective amount
of low molecular weight amphiphilic compounds which function as
viscosity control and gel-inhibiting agents for the nonionic
surfactant substantially improves the storage properties of the
composition. The amphiphilic compounds can be considered to be
analagous in chemical structure to the ethoxylated and/or
propoxylated fatty aclohol liquid nonionic surfactants but have
relatively short hydrocarbon chain lengths (C.sub.2 to C.sub.8) and
a low content of ethylene oxide (about 2 to 6 ethylene oxide groups
per molecule).
Suitable amphiphilic compounds can be represented by the following
general formula
where R is a C.sub.2 -C.sub.8 alkyl group, and n is a number of
from about 1 to 6, on average.
Specifically the compounds are lower (C.sub.2 to C.sub.3) alkylene
glycol mono lower (C.sub.2 to C.sub.5) alkyl ethers.
More specifically the compounds are mono di- or tri lower (C.sub.2
to C.sub.3) alkylene glycol mono lower (C.sub.1 to C.sub.5) alkyl
ethers.
Specific examples of suitable amphiphilic compounds include
ethylene glycol monoethyl ester C.sub.2 H.sub.5 --O--CH.sub.2
CH.sub.2 OH, diethylene glycol monobutyl ether C.sub.4 H.sub.9
--O--(CH.sub.2 CH.sub.2).sub.2 H, tetraethylene glycol monobutyl
ether C.sub.4 H.sub.7 --O--(CH.sub.2 CH.sub.2 O).sub.4 H and
dipropylene glycol monomethyl ether ##STR7## Diethylene glycol
monobutyl ether is especially preferred.
The inclusion in the composition of the low molecular weight lower
alkylene glycol mono alkyl ether decreases the viscosity of the
composition, such that it is more easily pourable, improves the
stability against settling and improves the dispersibility of the
composition on the addition to warm water or cold water.
The compositions of the present invention have improved viscosity
and stability characteristics and remain stable and pourable at
temperatures as low as about 5.degree. C. and lower.
Stabilizing Agents
In an embodiment of this invention the physical stability of the
suspension of the detergent builder compound or compounds and any
other suspended additive, such as bleaching agent, etc., in the
liquid vehicle is improved by the presence of a stabilizing agent
which is an alkanol ester of phosphoric acid or an aluminum salt of
a higher fatty acid.
Improvements in stability of the composition may be achieved in
certain formulations by incorporation of a small effective amount
of an acidic organic phosphorus compound having an acidic--POH
group, such as a partial ester of phosphorous acid and an
alkanol.
As disclosed in the commonly assigned copending application Ser.
No. 597,948 filed Apr. 9, 1984 the disclosure of which is
incorporated herein by reference, the acidic organic phoshorous
compound having an acidic--POH group can increase the stability of
the suspension of builders in the nonaqueous liquid nonionic
surfactant.
The acidic organic phosphorus compound may be, for instance, a
partial ester of phosphoric acid and an alcohol such as an alkanol
which has a lipophilic character, having, for intance, more than 5
carbon atoms, e.g. 8 to 20 carbon atoms.
A specific example is a partial ester of phosphoric acid and a
C.sub.16 to C.sub.18 alkanol (Empiphos 5632 from Marchon); it is
made up of about 35% monoester and 65% diester.
The inclusion of quite small amounts of the acidic organic
phosphorus compound makes the suspension significantly more stable
against settling on standing but remains pourable, while, for the
low concentration of stabilizer, e.g. below about 1%, its plastic
viscosity will generally decrease.
Further improvements in the stability and anti-settling properties
of the composition may be achieved by the addition of a small
effective amount of an aluminum salt of a higher fatty acid to the
composition.
The aluminum salt stabilizing agents are the subject matter of the
commonly assigned copending application Ser. No. 725,455, filed
Apr. 22, 1985, the disclosure of which is incorporated herein by
reference.
The preferred higher aliphatic fatty acids will have from about 8
to about 22 carbon atoms, more preferably from about 10 to 20
carbon atoms, and especially preferably from about 12 to 18 carbon
atoms. The aliphatic radical may be saturated or unsaturated and
may be straight or branched. As in the case of the nonionic
surfactants, mixtures of fatty acids may also be used, such as
those derived from natural sources, such as tallow fatty acid, coco
fatty acid, etc.
Examples of the fatty acids from which the aluminum salt
stabilizers can be formed include, decanoic acid, dodecanoic acid,
palmitic acid, myristic acid, stearic acid, oleic acid, eicosanoic
acid, tallow fatty acid, coco fatty acid, mixtures of these acids,
etc. The aluminum salts of these acids are generally commercially
available, and are preferably used in the triacid form, e.g.
aluminum stearate as aluminum tristearate Al(C.sub.17 H.sub.35
COO).sub.3. The monoacid salts, e.g. aluminum monostearate,
Al(OH).sub.2 (C.sub.17 H.sub.35 COO) and diacid salts, e.g.
aluminum distearate, Al(OH)(C.sub.17 H.sub.35 COO).sub.2, and
mixtures of two or three of the mono-, di- and triacid aluminum
salts can also be used. It is most preferred, however, that the
triacid aluminum salt comprises at least 30%, preferably at least
50%, especially preferably at least 80% of the total amount of
aluminum fatty acid salt.
The aluminum salts, as mentioned above, are commercially available
and can be easily produced by, for example, saponifying a fatty
acid, e.g. animal fat, stearic acid, etc., followed by treatment of
the resulting soap with alun, alumina, etc.
Although applicants do not wish to be bound by any particlar theory
of the manner by which the aluminum salt functions to prevent
settling of the suspended particles, it is presumed that the
aluminum salt increases the wettability of the solid surfaces by
the nonionic surfactant. This increase in wettability, therefore,
allows the suspended particles to more easily remain in
suspension.
Only very small amounts of the aluminum salt stabilizing agent is
required to obtain the significant improvements in physical
stability.
In addition to its action as a physical stabilizing agent, the
aluminum salt has the additional advantages over other physical
stabilizing agents that it is non-ionic in character and is
compatible with the nonionic surfactant component and does not
interfere with the overall detergency of the composition; it
exhibits some anti-foaming effect; it can function to boost the
activity of fabric softeners, and it confers a longer relaxation
time to the suspensions.
Bleaching Agents
The bleaching agents are classified broadly, for convenience, as
chlorine bleaches and oxygen bleaches. Chlorine bleaches are
typified by sodium hypochlorite (NaOCl), potassium
dichloroisocyanurate (59% available chlorine), and
trichloroisocyanuric acid (95% available chlorine). Oxygen bleaches
are preferred and are represented by percompounds which liberate
hydrogen peroxide in solution. Preferred examples include sodium
and potassium perborates, percarbonates, and perphosphates, and
potassium monopersulfate. The perborates, particularly sodium
perborate monohydrate, are especially preferred.
The peroxygen compound is preferably used in admixture with an
activator therefor. Suitable activators which can lower the
effective operating temperature of the peroxide bleaching agent are
disclosed, for example, in U.S. Pat. No. 4,264,466 or in column 1
of U.S. Pat. No. 4,430,244, the relevant disclosures of which are
incorporated herein by reference. Polyacylated compounds are
preferred activators; among these, compounds such as tetraacetyl
ethylene diamine ("TAED") and pentaacetyl glycose are particularly
preferred.
Other useful activators include, for example, acetylsalicylic acid
derivatives, ethylidene benzoate acetate and its salts, ethylidene
carboxylate acetate and its salts, alkyl and alkenyl succinic
anhydride, tetraacetylglycouril ("TAGU"), and the derivatives of
these. Other useful classes of activators are disclosed, for
example, in U.S. Pat. Nos. 4,111,826, 4,422,950 and 3,661,789.
The bleach activator usually interacts with the peroxygen compound
to form a peroxyacid bleaching agent in the wash water. It is
preferred to include a sequestering agent of high complexing power
to inhibit any undesired reaction between such peroxyacid and
hydrogen peroxide in the wash solution in the presence of metal
ions.
Suitable sequestering agents for this purpose include sodium salts
of nitrilotriacetic acid (NTA), ethylene diamine tetraacetic acid
(EDTA), diethylene triamine pentaacetic acid (DETPA), diethylene
triamine pentamethylene phosphonic acid (DTPMP) sold under the
tradename Dequest 2066; and ethylene diamine tetramethylene
phosphonic acid (EDITEMPA). The sequestering agents can be used
alone or in admixture.
In order to avoid loss of peroxide bleaching agent, e.g. sodium
perborate, resulting from enzyme-induced decomposition, such as by
catalase enzyme, the compositions may additionally include an
enzyme inhibitor compound, i.e. a compound capable of inhibiting
enzyme-induced decomposition of the peroxide bleaching agent.
Suitable inhibitor compounds are disclosed in U.S. Pat. No.
3,606,990, the relevant disclosure of which is incorporated herein
by reference.
Of special interest as the inhibitor compound, mention can be made
of hydroxylamine sulfate and other water-soluble hydroxylamine
salts. In the preferred nonaqueous compositions of this invention,
suitable amounts of the hydroxylamine salt inhibitors can be as low
as about 0.01 to 0.4%. Generally, however, suitable amounts of
enzyme inhibitors are up to about 15%, for example, 0.1 to 10%, by
weight of the composition.
In addition to the detergent builders, various other detergent
additives or adjuvants may be present in the detergent product to
give it additional desired properties, either of functional or
aesthetic nature. Thus, there may be included in the formulation,
minor amounts of soil suspending or anti-redeposition agents, e.g.
polyvinyl alcohol, fatty amides, sodium carboxymethyl cellulose,
hydroxy-propyl methyl cellulose. A preferred anti-redeposition
agent is sodium carboxymethyl cellulose having a 2:1 ratio of CM/MC
which is sold under the tradename Relatin DM 4050.
Optical brighteners for cotton, polyamide and polyester fabrics can
be used. Suitable optical brighteners include stilbene, triazole
and benzidine sulfone compositions, especially sulfonated
substituted triazinyl stilbene, sulfonated naphthotriazole
stilbene, benzidene sulfone, etc., most preferred are stilbene and
triazole combinations. A preferred brightener is Stilbene
Brightener N4 which is a dianilinodimorpholino stilbene
polysulfonate.
Enzymes, preferably proteolytic enzymes, such as subtilisin,
bromelin, papain, trypsin and pepsin, as well as amylase type
anzymes, lipase type enzymes, and mixtures thereof can be used.
Preferred enzymes include protease slurry, esperase slurry and
amylase. A preferred enzyme is Esperse SL8 which is a protease.
Anti-foam agents, e.g. silicon compounds, such as Silicane L 7604,
which is a polysiloxane can also be added in small effective
amounts.
Bactericides, e.g. tetrachlorosalicylanilide and hexachlorophene,
fungicides, dyes, pigments (water dispersible), preservatives,
ultraviolet absorbers, anti-yellowing agents, such as sodium
carboxymethyl cellulose, pH modifiers and pH buffers, color safe
bleaches, perfume, and dyes and bluing agents such as ultramarine
blue can be used.
The composition may also contain an inorganic insoluble thickening
agent or dispersant of very high surface area such as finely
divided silica of extremely fine particle size (e.g. of 5-100
millimicrons diameters such as sold under the name Aerosil) or the
other highly voluminous inorganic carrier materials disclosed in
U.S. Pat. No. 3,630,929, in proportions of 0.1-10%, e.g. 1 to 5%.
It is preferable, however, that compositions which form peroxyacids
in the wash bath (e.g. compositions containing peroxygen compound
and activator therefor) be substantially free of such compounds and
of other silicates; it has been found, for instance, that silica
and silicates promote the undesired decomposition of the
peroxyacid.
In an embodiment of the invention the stability of the builder
salts in the composition during storage and the dispersibility of
the composition in water is improved by grinding and reducing the
particle size of the solid builders is less than 100 microns,
preferably less than 40 microns and more preferably to less than 10
microns. The solid builders are generally supplied in particle
sizes of about 100, 200 or 400 microns. The nonionic liquid
surfactant phase can be mixed with the solid builders prior to or
after carrying out the grinding operation.
In a preferred embodiment of the invention, the mixture of liquid
nonionic surfactant and solid ingredients is subjected to an
attrition type of mill in which the particle sizes of the solid
ingredients are reduced to less than about 10 microns, e.g. to an
average particle size of 2 to 10 microns or even lower (e.g. 1
micron). Preferably less than about 10%, especially less than about
5% of all the suspended particles have particle sizes greater than
10 microns. Compositions whose dispersed particles are of such
small size have improved stability against separation or settling
on storage. Addition of the acid terminated nonionic surfactant
compound aids in the dispersibility of the dispersions without a
correspoding decrease in the dispersions stability against
settling.
In the grinding operation, it is preferred that the proportion of
solid ingredients be high enough (e.g. at least about 40% such as
about 50%) that the solid particles are in contact with each other
and are not substantially shielded from one another by the nonionic
surfactant liquid. After the grinding step any remaining liquid
nonionic surfactant can be added to the ground formulation. Mills
which employ grinding balls (ball mills) or similar mobile grinding
elements have given very good results. Thus, one may use a
laboratory batch attritor having 8 mm diameter steatite grinding
balls. For larger scale work a continuously operating mill in which
there are 1 mm or 1.5 mm diameter grinding balls working in a very
small gap between a stator and a rotor operating at a relatively
high speed (e.g. a CoBall mill) may be employed; when using such a
mill, it is desirable to pass the blend of nonionic surfactant and
solids first through a mill which does not effect such fine
grinding (e.g. a colloid mill) to reduce the particle size to less
than 100 microns (e.g. to about 40 microns) prior to the step of
grinding to an average particle diameter below about 10 microns in
the continuous ball mill.
In the preferred heavy duty liquid laundry detergent compositions
of the invention, typical proportions (percent based on the total
weight of composition, unless otherwise specified) of the
ingredients are as follows:
Liquid nonionic surfactant detergent in the range of about 20 to
60, such as 25 to 50 percent.
Acid terminated nonionic surfactant may be omitted, it is preferred
however that it be added to the composition in an amount in the
range of about 2 to 30, such as 5 to 30 and 10 to 25 percent.
Polyacetal carboxylate acid builder salt in the range of about 5 to
50, such as 10 to 30 percent.
Polyphosphate detergent builder salt in the range of about 0 to 30
percent, such as 0 to 20 percent and 5 to 15 percent.
Copolymer of polyacrylate and polymaleic anhydride alkali metal
salt anti incrustation agent in the range of about 0 to 10, such as
2 to 8 percent.
Alkylene glycol monoalkylether anti-gel agent in an amount in the
range of about 0 to 20, such as 5 to 15 percent.
Phosphoric acid alkanol ester stabilizing agent in the range of 0
to 2.0 or 0.1 to 2.0, such as 0.10 to 1.0 and 0.10 to 0.5
percent.
Aluminum salt of fatty acid stabilizing agent in the range of about
0 to 3.0, such as 0.1 to 1.0 percent.
It is preferred that at least one of phosphoric acid ester or
aluminum salt stabilizing agents be included in the
composition.
Bleaching agent in the range of about 0 to 35, such as 5 to 30
percent.
Bleach activator in the range of about 0 to 25, such as 5 to 20
percent.
Sequestering agent for bleach in the range of about 0 to 3.0,
preferably 0.5 to 2.0 percent.
Anti-redeposition agent in the range of about 0 to 3.0, preferably
0.5 to 2.0 percent.
Optical brightener in the range of about 0 to 2.0, preferably 0.1
to 1.5 percent.
Enzymes in the range of about 0 to 3.0, preferably 0.5 to 2.0
percent.
Perfume in the range of about 0 to 2.0, preferably 0.10 to 1.0
percent.
Various of the previously mentioned additives can optionally be
added to achieve the desired function of the added materials.
Mixtures of the acid terminated nonionic surfactant and the
alkylene glycol alkyl ether anti-gel agents can be used and in some
cases advantages can be obtained by the use of such mixtures alone,
or with the addition to the mixture of a stabilizing and anti
settling agent.
In the selection of the additives, they will be chosen to be
compatible with the main constituents of the detergent composition.
In this application, as mentioned above, all proportions and
percentages are by weight of the entire formulation or composition
unless otherwise indicated.
The concentrated nonaqueous nonionic liquid detergent composition
of the present invention dispenses readily in the water in the
washing machine. The presently used home washing machines normally
use 175 gms of powder detergent to wash a full load of laundry. In
accordance with the present invention only about 67 ml or about 80
gms of the concentrated liquid nonionic detergent composition is
needed.
In a preferred embodiment of the invention the detergent
composition of a typical formulation is formulated using the below
named ingredients:
______________________________________ Weight %
______________________________________ Nonionic surfactant
detergent. 30-55 Acid terminated surfactant. 2-18 Alkali metal
polyacetal carboxylic acid builder salt. 5-22 Polyphosphate builder
salt. 0-20 Alkanol phosphoric acid ester. 0.1-0.9 Alkali metal
perborate bleaching agent. 7-22 Bleach activator (TAED). 4-12
Optical brightener (Stilbene Brightener N4). 0.1-0.8 Enzymes
(Protease-Esperase SL8). 0.5-1.5 Perfume. 0.1-0.8
______________________________________
The present invention is further illustrated by the following
example.
EXAMPLE
A concentrated nonaqueous liquid nonionic surfactant detergent
composition is formulated from the following ingredients in the
amounts specified.
______________________________________ Weight %
______________________________________ Product D nonionic
surfactant. 40.0 Acid terminated Dobanol 91-5 reaction product with
14.0 succinic anhydride. Sodium salt of polyacetal carboxylic acid
(Builder U). 17.0 Alkanol phosphoric acid ester. 0.3 Sodium
perborate monohydrate bleaching agent. 17.0 Tetraacetylethylene
diamine (TAED) bleach activator. 10.0 Stilbene brightener N4. 0.4
Esperase slurry. 1.0 Perfume. 0.3 100.000
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The formulation is ground for about one hour to reduce the particle
size of the suspended builder salts to less than 10 microns. The
formulated detergent composition is found to be stable and
non-gelling in storage and to have a high detergent capacity.
The formulations can be prepared without grinding the builder salts
and suspended solid particles to a small particle size, but best
results are obtained by grinding the formulation to reduce the
particle size of the suspended solid particles.
The builder salts can be used as provided, or the builder salts and
suspended solid particles can be ground or partially ground prior
to mixing them with the nonionic surfactant. The grinding can be
carried out in part prior to mixing and grinding completed after
mixing or the entire grinding operation can be carried out after
mixing with the liquid surfactant. The formulations containing
suspended builder and solid particles less than 10 microns in size
are preferred.
It is understood that the foregoing detailed description is given
merely by way of illustration and that variations may be made
therein without departing from the spirit of the invention.
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